Whole-home duct cleaning
Dryer vent cleaning
Camera inspection
Sanitizing & deodorizingWhole-system duct and dryer vent check with before-and-after photos - you see exactly what came out of your vents
That "$99 whole-house special" is a bait ad - the real number appears once they are in your hallway, or the "clean" is a shop-vac at the register. We photograph the inside of your ducts before and after instead.
Fast, Reliable Duct Sealing Across Downtown Los Angeles
Duct sealing in Downtown Los Angeles typically runs $850 to $2,400 depending on system size, access, and whether we’re working in a single-unit loft or a high-rise with shared risers. Most jobs in DTLA take one full day from setup to cleanup. If you’re breathing dust from a neighbor’s renovation or your AC can’t hold temperature on Spring Street in August, call us at (626) 469-5477 for a written quote before any work starts.
We know this neighborhood’s buildings from the inside out. Our crews work the freight elevators, coordinate with building management, and understand what it takes to seal ducts in buildings that were wired and vented before most of our competitors existed at all.
Why Hollis Air Duct Pasadena Is Downtown Los Angeles’s Preferred Duct Sealing Company
Roy Castellanos leads our team, and the standard he set has not moved since 2004: the price is written before we touch a duct, the crew arrives uniformed and background-checked, and the job is done by the book. Downtown Los Angeles building managers and condo boards want exactly that. They don’t want a variable bill or a crew that can’t get through the loading dock without a hassle. They want a vendor who can show credentials, stay inside the window, and leave the mechanical room cleaner than they found it.
Our work in Downtown Los Angeles runs heavy on one building type: converted industrial lofts and pre-war high-rises with original galvanized ductwork. That is not a profile most duct companies see in a year. We see it weekly. We know which buildings in the Historic Core have risers that cross units, which parking situations force us to bring equipment in through a narrow freight elevator, and which building engineers need sign-off before we start. That local knowledge means the job gets quoted accurately the first time and the bid holds.
Every Downtown Los Angeles job carries the 365-Day Done Right Promise in writing. If the seal fails inside a year, we return and redo it at no charge, including a free second visit. We don’t ask for a punch list or a negotiation. The promise is on the paperwork, same as the price.
Styles & brands we work with
HVAC Duct Sealing in Downtown Los Angeles
HVAC Duct Sealing in Downtown Los Angeles means finding and closing every leak in the supply and return duct run so the air you pay to cool actually reaches the rooms instead of bleeding into a mechanical shaft, a dropped ceiling, or the space behind a wall. In DTLA’s converted lofts, the leaks are often in the riser joints, the connections at the air handler, and the seams of original galvanized ducts that have flexed and separated over decades. We run the system under pressure, find the losses, and seal them with mastic or foil tape rated for the job. A typical condo or loft unit runs $850 to $1,600. A larger unit with accessible riser work can run $1,800 to $2,400.
Pressure Testing the System
We measure the leak rate before and after. That number is what tells us the seal worked. Without a pressure test, you’re paying for an opinion.
Sealing Materials and Methods
We use mastic sealant at every accessible joint and metal-backed tape where the gaps are small. For air handlers and plenums, we seal with a brush-on fiberglass-reinforced mastic that holds under the temperature swings common in Downtown Los Angeles high-rises.
Duct Repair in Downtown Los Angeles
Duct Repair in Downtown Los Angeles is usually not a single hole. It’s three or four things: a collapsed section of flex duct behind a wall, a separated joint at a riser, a crushed return under a remodeled kitchen island. We find the full picture before we quote, because half a repair on a shared system does not fix the leak. Repair work in DTLA runs $450 to $1,200 for accessible sections, more if we need to open a wall or coordinate with building engineering.
Repairing Original Galvanized Risers
Original galvanized risers in pre-war buildings often separate at the flanges. We re-align, re-gasket, and seal those connections mechanically, not just with tape. A taped joint on a riser fails within months. A re-gasketed joint holds.
Repairing Damaged Flex Runs
Flex duct in many converted units has been crushed by later construction, telecom installs, or storage. We replace those short runs with correctly sized duct and seal the connections at both ends. That fix alone can restore static pressure to a bedroom that never cooled properly.
Trusted Brands We Service in Downtown Los Angeles
We service and seal systems built around equipment from Aprilaire, Abatement Technologies, and Rotobrush. Our Duct Sealing crews run Rotobrush rotary brush systems and Abatement Technologies negative-air machines on Downtown Los Angeles jobs, and we stock Aprilaire filter frames and media locally so your system stays sealed and clean after we leave. When a Downtown Los Angeles building manager asks us to match a specific filter spec or equipment standard, the answer is usually already in the van because we preloaded for the job based on the building’s known equipment.
See the difference
Before
After
Before
After
Before
AfterCommon Duct Sealing Problems We See in Downtown Los Angeles Homes
- Shared riser leaks. In many Historic Core and Arts District buildings, your supply duct runs through a riser that serves multiple units. A leak in a neighbor’s duct can push dust and cooking odors into your air stream. We seal what is accessible on your side and document the rest for building management.
- Freight elevator constraints. Equipment has to break down to fit. We bring compact negative-air machines and rotary brush systems sized for freight elevators and tight mechanical rooms. The gear arrives on carts, not dollies that don’t fit the door.
- Original galvanized corrosion. Decades of urban soot and temperature cycles corrode the inside of original ducts. That corrosion creates pinhole leaks and rough surfaces that hold dust. We identify it with a camera before sealing, so we’re not sealing over a failing section.
- Building management access rules. Some riser sections sit behind locked doors controlled by the building. We coordinate with management before the job is priced, not after, so the scope includes what can actually be reached. If management won’t grant access, the written quote reflects that limitation.
Pricing for Duct Sealing in Downtown Los Angeles, CA
HVAC duct sealing in Downtown Los Angeles runs $850 to $1,600 for a typical single-unit loft or condo. Larger units, multi-zone systems, or jobs with significant riser access run $1,800 to $2,400. Duct repair runs $450 to $1,200 depending on access and what has to be replaced. What moves the price in DTLA specifically is freight elevator scheduling, building management coordination, and how much of the riser is accessible. We write the full price before work starts and it does not move. Call (626) 469-5477 for a free estimate based on your building’s actual conditions, not a generic brochure.
We Also Serve Cities Near Downtown Los Angeles
Our crews work throughout the metro, including Pasadena, Glendale, Burbank, and East Los Angeles. If you’re in one of those cities and need duct sealing with the same written-price standard, call (626) 469-5477 and we’ll schedule from our Los Angeles-area office.
Serving Downtown Los Angeles, CA - Our Local Coverage Area
We’re based in the Downtown Los Angeles area and know this community well. Use the map below to see our service coverage - if you’re nearby, we can almost certainly help.
FAQs About Duct Sealing in Downtown Los Angeles
Shared risers mean a seal in your unit can be compromised by leaks from adjacent units feeding dust into the same shaft. We seal every accessible joint on your side, document the condition of the shared run, and report what’s happening above or below you so the building can act. In some buildings we can coordinate with management to seal the full riser run, which is the only way to fully stop cross-unit contamination. Call (626) 469-5477 and we’ll tell you whether your building has this configuration and what’s realistic.
Yes, partially. Sealing the return side of the system stops negative pressure from pulling dust through gaps in the ducts themselves. But if the dust is entering through windows, door gaps, or unsealed wall penetrations, duct sealing alone won’t stop it. We inspect the full path and tell you what the duct work can and can’t fix before quoting.
Our standard Downtown Los Angeles setup includes compact negative-air machines from Abatement Technologies and Rotobrush rotary brush systems that break down to fit a standard freight elevator. We don’t need a loading dock or street-level access. If your building requires a Certificate of Insurance or advance scheduling, we handle that before the job date.
Yes. Original galvanized ducts in pre-war and adaptive-reuse buildings are thinner than modern sheet metal and often corroded at the seams. We use a combination of mechanical reconnection, mastic, and metal tape rated for those materials. Some Historic Building Code restrictions limit alteration of original ductwork, so we work within what is permitted and document any sections that remain unsealed due to those rules.
In Downtown Los Angeles, where AC runs hard May through October and buildings experience temperature swings, a properly sealed duct system typically holds for 10 to 15 years. The vulnerable points are the joints we could not access due to building restrictions. That’s why we give you a written map of what was sealed and what wasn’t. Our 365-Day Done Right Promise covers any failure in the first year, including a free return visit.
Call (626) 469-5477 for a free estimate on duct sealing in Downtown Los Angeles. Roy Castellanos and our team will send a background-checked, uniformed crew with a written price before any work begins. That’s the whole deal.
Written by Roy Castellanos, Owner at Hollis Air Duct Pasadena, serving Downtown Los Angeles with The Garrison Standard since 2004.